Virtualization News Archives

The Kernel-based Virtual Machine (KVM) changes were sent out on Thursday for the Linux 6.7 merge window.

While confidential computing is a hot area right now, there's been a limited amount of cross-vendor cooperation with AMD having their own route with Secure Encrypted Virtualization (SEV) and Intel designing the Trusted Domain Extensions (TDX) that is still available in limited form. As one improvement coming with Linux 6.7, "configfs-tsm" has been submitted for pulling as a cross-vendor solution for confidential computing attestation reports.

Both AMD and Intel engineers have experienced a lengthy journey getting their latest virtualization security features into the mainline Linux kernel -- and one that is still ongoing.

Back in August Linux Containers forked the LXD project as Incus following Canonical's decision to take in control of LXD. Released this weekend was the first formal release for the Incus software.

The past several Linux kernel cycles has seen Loongson engineers working on implementing more kernel features for LoongArch, the MIPS-derived and RISC-V-inspired architecture out of China for domestic PCs. The performance of LoongArch CPUs so far still aren't competitive to x86_64 or Arm hardware but at least slowly are becoming more practical with more features being wired up. The latest milestone is the Kernel-based Virtual Machine (KVM) virtualization support appearing ready ahead of Linux 6.7.

Cloud Hypervisor 35 was released on Thursday for this open-source, Rust-based VMM that was originally started by Intel software engineers before evolving into a multi-vendor initiative for secure and cloud focused workloads.

Merged on Thursday were a batch of KVM virtualization changes for the Linux 6.6 kernel.

Microsoft continues improving the Hyper-V support within the Linux kernel for benefiting Linux guest VMs running within this hypervisor on Windows. With Linux 6.6 the Hyper-V code adds support for SEV-SNP secure guests on the AMD EPYC side while over on the Intel Xeon Scalable Sapphire Rapids side is initial support for Trust Domain Extensions (TDX) protected guests.

QEMU 8.1 is now available as the latest feature update to this important piece of the open-source Linux virtualization stack.

Cloud Hypervisor -- the Rust-written open-source VMM that was started by Intel while having evolved into a Linux Foundation project with backing from multiple organizations -- is out with the Cloud-Hypervisor 34 release.

There is a phenomenon where running a multi-threaded workload inside a virtual machine (VM) with Simultaneously Multi-Threading (SMT / Intel Hyper Threading) that a sibling thread could find itself busy while the CPU core is idle. A new Linux CFS patch series aims to make the scheduler better adapt to the QEMU topology.

As was anticipated, UEFI Unaccepted Memory support was successfully merged for Linux 6.5 to support this standard that's important with the likes of Intel Trusted Domain Extensions (TDX) and AMD Secure Encrypted Virtualization Secure Nested Page (SEV-SNP) backed virtual machines.

The Kernel-based Virtual Machine (KVM) changes were submitted today that are ready for introduction in the Linux 6.5 kernel.

The Virtual Function I/O "VFIO" changes were merged last week for the ongoing Linux 6.5 kernel merge window. This IOMMU/device agnostic framework has added an AMD CDX driver this cycle along with other improvements for this subsystem that is important to the Linux virtualization stack.

Cloud Hypervisor has advanced quite nicely in the half-year it's been around since Intel software engineers began writing this Rust-based cloud-focused virtualization hypervisor. This VMM project has since become more independent and regularly receiving code contributions from the likes of Arm, Microsoft, and Tencent while also gaining the support of companies like AMD and Ampere. On Thursday marked the release of Cloud Hypervisor 33.

Google engineers have been working on Linux patches to improve the guest VM performance when the host encounters memory pressure or have over-committed too many guests. Similar patches already are used on Chrome OS and Google has been working to upstream the functionality under the mainline Linux kernel and have now provided some reference benchmark results.

For over two years Intel open-source engineers have been working on preparing the Linux kernel for UEFI unaccepted memory support and it looks like that will cross the finish line with the upcoming Linux 6.5 cycle.

Queued via drm-misc-next and now on its way to DRM-Next ahead of the upcoming Linux 6.5 cycle is support in the VirtIO GPU DRM driver for the synchronization object user-space API. This is important for Vulkan and is working with the Venus/Virgl driver context as well as Intel/AMDGPU/Freedreno native contexts too.

The Virgl driver within Mesa for allowing open-source OpenGL support within virtualized environments in conjunction with the Virglrenderer is now capable of exposing OpenGL 4.6.

An updated set of patches were posted on Friday that seem to improve the Linux guest VM performance when the host is under heavy memory pressure.

Released this week from the Red Hat Summit is Podman Desktop 1.0 as a container management tool akin to Docker Desktop.

Adding to the list of features coming with QEMU 8.1 is now having a native PipeWire audio back-end.

Near the start of 2022 engineers out of the Qualcomm Innovation Center posted Linux driver patches for their Gunyah hypervisor. Gunyah is an open-source type-1 hypervisor developed by Qualcomm with an emphasis on security and other features. More than one year later the Gunyah drivers have yet to be upstreamed into the mainline Linux kernel but work on them persists.

QEMU 8.0 is out today as the newest feature release for this processor emulator that plays an important role in the open-source Linux virtualization stack.

Cloud Hypervisor 31 was released this week as the Rust-written VMM started by Intel that runs atop Linux KVM and Microsoft MSHV while these days is a Linux Foundation project receiving regular contributions from not only Intel and Microsoft but also Tencent, Arm, and other players.

Google engineers on Thursday posted initial "request for comments" patches on their KVM-CPUFreq driver that is part of their effort to improve the dynamic voltage and frequency scaling behavior and task placement within KVM-based virtual machines. This effort is leading to big improvements in raw performance and performance-per-Watt for tasks running within Linux VMs.

The focus of this new effort isn't to immediately rewrite the Xen virtualization hypervisor in Rust but to begin gradually working toward rewriting some of the smaller Xen Project components in the Rust programming language and to see how everything pans out.

A lot of Kernel-based Virtual Machine (KVM) updates were merged for the Linux 6.3 cycle to further enhance the open-source virtualization stack.

Cloud Hypervisor as a reminder is what started out as an open-source Intel project to develop a modern hypervisor focused on cloud workloads and with security being among the leading concerns. Cloud Hypervisor more recently is developed as a Linux Foundation project but with Intel's software engineers being among the leading contributors to the project along with the likes of Arm, Tencent, Bytedance, and Microsoft.

Several months back I wrote about Microsoft working on nested hypervisor support for Hyper-V with the Linux kernel. That work is now ready to go for the in-development Linux 6.3 cycle.

Google engineer Yu Zhao known for his work on MGLRU has published a new patch series today that "significantly improves" the KVM guest performance when the host system is under heavy memory pressure.

While LoongArch merged for Linux 5.19 last year, that initial kernel port to the Chinese CPU architecture wasn't entirely complete and some Loongson 3A5000 features are still being enabled for the mainline kernel. The latest feature work being carried out by Loongson engineers is for supporting hardware virtualization on the 3A5000 processors with KVM.

Libvirt 9.0 was released on Monday as the newest version of this Linux Virtualization API. This virtualization API backed by Red Hat continues to support a wide range of hypervisors and with the v9.0 release has added additional functionality.

Cloud Hypervisor 29.0 has been released as the open-source virtualization hypervisor that was started by Intel but then began seeing support by the likes of Microsoft and Arm. Cloud Hypervisor was since spunoff to the Linux Foundation where it continues seeing more industry support by the likes of AMD and Ampere.

Ampere Computing is the latest major vendor now backing the Cloud Hypervisor Project hosted by the Linux Foundation as a Rust-written VMM focused on running modern cloud workloads in a fast and secure manner.

The initial batch of feature updates for the Kernel-based Virtual Machine (KVM) have been submitted for the Linux 6.2 merge window.

The QEMU open-source emulator that plays an important role in the Linux virtualization stack is out with its version 7.2 release ahead of the Christmas holidays.

After being in various forms of discussion since 2017, IOMMUFD has been submitted for the Linux 6.2 kernel as it lays the groundwork for aiming to overhaul IOMMU handling by QEMU and virtual machines on Linux.

Cloud Hypervisor as the open-source, Rust-written and modern hypervisor project that was started by Intel and now also backed by AMD, Arm, Microsoft, and other vendors is out with a big release.

QEMU 7.2 is gearing up for release in December as the next feature release to this widely-used processor emulator by the Linux virtualization stack. QEMU 7.2-rc1 is available for testing with a number of new features and improvements coming in this release.

Anbox Cloud as Canonical's solution for Android containers in the cloud is out with a shiny new feature release.

The Xen hypervisor changes were merged this week for the Linux 6.1 kernel merge window that is wrapping up this weekend.

The VirtIO changes were merged this week for the Linux 6.1 merge window that is ending this weekend.

The 9P network protocol is commonly used -- such as with QEMU's 9pfs pass-through file-system -- for being able to share certain directories/files on host machines with the guest operating systems. With Linux 6.1 the 9p code has seen a nice set of optimizations that can allow for faster communication between the host and guest(s).

At last week's XDC 2022 conference, Google engineer Rob Clark presented on VirtGPU DRM Native Contexts and the potential there for much better performance - especially for gaming - within virtual machines than using API-level virtualization like with Virgl.

It's been a long time since last having anything significant to report on for Oracle's VM VirtualBox software: VirtualBox 6.0 debuted in 2018 and VirtualBox 6.1 in 2019, but since has been rather quiet... But out today is now VirtualBox 7.0 with big features like support for full virtual machine encryption and a new Direct3D 11 based graphics stack, which for Linux use is now going through DXVK.

Cloud-Hypervisor as what started as an open-source project by Intel and now run under the Linux Foundation umbrella as a Rust-based, modern-focused hypervisor for cloud workloads keeps on advancing. In addition to Intel, Microsoft and Arm continue investing significant resources into Cloud-Hypervisor for this security-focused VMM for running Windows and Linux guests.

QEMU 7.1 is now available as the latest feature release for this processor emulator that plays an important role in the open-source Linux virtualization stack.

Cloud Hypervisor 26.0 released this week as the newest version of this Rust-based hypervisor focused on cloud workloads and secure computing. The open-source Cloud Hypervisor started out as an Intel software project and continues to be led by them while now under Linux Foundation stewardship and continuing to see contributions from the likes of Arm and Microsoft.

A number of changes were merged into Linux 6.0 for benefiting virtualization when making use of VirtIO.